First source: Mr. George Knapp, KLAS, in the video story here: Documents prove secret UFO study based in Nevada. The source of the actual documents shown where Bigelow Aerospace Advanced Space Studies is filled out in the awarded contract, is unknown and not sourced.
Second source: Although the above story did not exactly time stamp the date of the contract being awarded, The Black Vault received a document via the Freedom of Information Act (FOIA) likely indicating the exact date. That document can be found at this PDF with the relevant citations being:
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